[GraphHopper] Why not using OSM way uid?

[Peter K]

Exactly, an edge is just a connection between two junctions.

Also have a look into the Java Magazine article
<http://karussell.wordpress.com/2014/01/23/graphhopper-news-article-in-java-magazine-and-fosdem-2014/>
where I described this issue. E.g. using osm ids would require us to use
a HashMap which requires more RAM (in an array you don't need to store
the indices!) and is potentially slower than an array.

If you need them nevertheless you can create a file on disc while import
to map internal ints to OSM long IDs

> non deterministic edge IDs.

BTW: these IDs are deterministic in a sense that an identical OSM file
produces exactly the same graph file with the same IDs. No random
behaviour involved!

Regards,
Peter.

>> I was just wondering why the OSM UIDs are not used instead of iterative
>> self generated non deterministic edge IDs.
> Because a single OSM way ID might yield more than one edge?
>
> Bye
> Frederik
>

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